docs: def structure_path(self, path):
          """Provide pointers to the paths of the structure file
  
          Args:
              path: Path to structure file
  
          """
          if not path:
              self.structure_dir = None
              self.structure_file = None
  
          else:
              if not op.exists(path):
                  raise OSError('{}: file does not exist!'.format(path))
  
              if not op.dirname(path):
                  self.structure_dir = '.'
              else:
                  self.structure_dir = op.dirname(path)
              self.structure_file = op.basename(path)